1. Field of the Invention
The present invention relates to liquid propellant fuels. More particularly the present invention relates to fuels for missile propellant applications. By way of further particularization the invention may be described as a general purpose completely hydrogenated hydrocarbon fuel.
2. Description of the Prior Art
There is a need for tactical air-launched missiles with significantly greater range capability. Because they utilize atmospheric oxygen as the oxidizer, air-breathing propulsion systems are more volumetrically efficient than conventional bipropellant liquid or solid propellant rockets for a given missile size and thus have the potential to fill this need. Even so air launched tactical missiles are quite volume limited, and therefore the most desirable fuels for this type missile system are those that contribute the most range per unit volume.
A comparison of readily available liquid fuels suitable for use as air breather fuels indicate that hydrocarbons exhibit the highest heat of combustion. Although the heat of combustion of hydrocarbons may vary considerably, in general the volumetric heat of combustion of a liquid hydrocarbon increases with an increasing carbon to hydrogen ratio. Also, the viscosity generally increases as the density increases, and an acceptable compromise must be made to minimize pumping and injection requirements while maintaining maximum heating value.
Isomers of tetrahydromethylcyclopentadiene dimer (TH-dimer) and exo-tetrahydrodicyclopentadiene (Exo-THDC) are fuels known in the art, but each has its limitations. Exo-THDC has a low flash point and TH-dimer has high viscosity. The Navy has a requirement for a fuel which has viscosity as low as possible and a flash point of at least 60.degree. C. or greater.